I. Field of the Invention
The present invention relates to satellite communications. More particularly, the present invention relates to the transmission of audio tones in an asynchronous transfer mode satellite network.
II. Description of the Related Art
Typically, cellular telephones emit various audio tones to indicate the status of a telephone call. For example, a xe2x80x9ccongestedxe2x80x9d tone indicates that the system cannot take additional traffic and a xe2x80x9cbusyxe2x80x9d tone indicates that the called party""s telephone is off-hook. These tones give the subscriber feedback on various operations of the telephone.
In order to transmit these audio tones in an asynchronous transfer mode (ATM) based satellite network that is designed to support switched voice traffic, separate virtual ATM channels are used to send a tone to the subscriber. This ties up a substantial amount of bandwidth that cannot be used for other voice traffic. This decreases the revenue generating resources of the service carrier. Additional equipment is also needed to transmit these tones. There is a resulting need for an optimized process for transmitting tones in an ATM network.
The present invention encompasses a process for providing an audio tone to a remote terminal. The remote terminal has access to at least one broadcast tone that has a unique identification associated with each tone. The remote terminal has communication capability with a control center.
The process begins by the control center receiving a request from the remote terminal to set up a call. At this point, the control center may be experiencing congestion and cannot grant the call set-up request.
The control center then informs the remote terminal of the identification of a broadcast tone communication path in response to the call set-up request. The remote terminal watches for this identification in the received ATM cells to find the tone.